Northern Long-Eared Bats

By Crystal Cockman

November 29, 2016

The northern long-eared bat or northern myotis (Myotis septentrionalis) is federally listed as a threatened species under the Endangered Species Act. Endangered species are species that are in danger of becoming extinct, and threatened species are species that are likely to become endangered. Up until a few years ago, these bats were plentiful throughout their range, but unfortunately they have been one of several bats negatively effected by White-nosed Syndrome (WNS). In some parts of their range, their population has decreased by as much as 99 percent.

Northern long-eared bats are native to North America, and are found throughout the eastern half of the United States and Canada from Manitoba and Newfoundland down to North Carolina and Alabama in the south. They are a medium bat in size, up to 3.5 inches, including a tail about 1.5 inches in length, and have a wingspan of 9-10 inches. Their fur color is light to medium brown, and they have distinctive long ears as their name suggests.

They spend winter hibernating in caves or mines, and in the summer they roost in cavities or crevices, particularly under bark, of living or dead trees. They sometimes roost in structures, such as barns or sheds. Males and nonreproductive females nest alone or in small groups, but reproductive female bats and their young nest in maternal colonies of up to 60 bats or more.

Breeding occurs in late summer or early fall, and after mating females store sperm during hibernation until spring. After hibernation, they ovulate and the stored sperm fertilizes an egg, a process known as delayed fertilization. Females give birth to a single pup, sometime between late May and late July, depending on what part of their range they live. They fly through forested areas to feed, mostly on moths, but also on beetles, flies, caddisflies, and other insects.

White-nosed fungus was first discovered in New York in 2006. Since then it has spread to the Midwest and Southeast. Pseudogymnoascus destructans is the fungus that causes WNS. WNS is named for the white fungus that appears on the muzzle and other parts of hibernating bats. The North Carolina Wildlife Resources Commission (NCWRC) and the United States Fish and Wildlife Service (USFWS) monitor caves and mines for white-nosed syndrome in North Carolina. The NCWRC began studying old gold mine shafts in the Uwharries a few years ago, and found white-nosed fungus in a cave in Stanly County.

Probably the biggest thing that can be done to stop the spread of white-nosed fungus is for people who go into caves or mines in contaminated areas to not wear contaminated clothing in areas where white-nosed fungus does not currently exist. In fact, it is recommended that people stay out of caves or mines altogether where bats are known to hibernate when bats are hibernating, in the winter. You can also report unusual bat behavior to NCWRC, such as bats flying around in the daytime or bats unable to fly or struggling to get off the ground. You can visit https://www.whitenosesyndrome.org/ to learn more about how you can help in the effort to protect bats like the northern long-eared bat and others.